Low-leakage air valve for variable air intake system

Abstract

A low-leakage air valve assembly 10 for an air intake manifold 16 includes a butterfly valve 12 constructed for mounting on a rotatable shaft 14. The butterfly valve 12 includes a first 32 and a second wing 34 with first elastic sealing means 36 mounted about the periphery of the first wing 32, and second elastic sealing means 40 mounted about the periphery of the second wing 34. The first elastic sealing means 32 includes a projecting lip 38 for sealingly contacting the wall of the valve manifold 16. The second elastic sealing means 40 includes a beam portion 42 for sealing contact with shoulder 28 of manifold 16. Third elastic sealing means 44 is axially positioned at each side of the passage 30 in the butterfly valve 12 and radially provided around a portion thereof. The first area 54 defined by the first sealing surface which is the first wing 32 and first elastic sealing means 36 is larger than the second area 56 defined by the second wing 34 and second elastic sealing means 40. This provides a net torque which increases the sealing force of the valve.

I claim: 
     
       1. A low-leakage air valve assembly for an air intake manifold, comprising: a valve manifold, said valve manifold having a plurality of ports therethrough, each port being defined by a perimeter having a shoulder on one side thereof and a shelf on an opposite side wall contoured radially about an upper edge thereof, said valve manifold including a channel extending axially across said valve manifold;   a shaft constructed for mounting in said channel of said valve manifold; and   a plurality of butterfly valves selectively spaced on said shaft to provide one butterfly valve for each port, each butterfly valve having a passage fairly centrally axially located therethrough for receiving said shaft therein, each butterfly valve having a first and second wing on each side of said passage, each of said wings having a periphery constructed to sealingly contact the perimeter of the port in the valve manifold for providing a sealing fit of said butterfly valve within the port in the valve manifold, said first wing of said butterfly valve having first elastic sealing means mounted on the periphery thereof for providing a fairly low-leakage air seal within the valve manifold, each of said first elastic sealing means being constructed of an elastic material and including a projecting lip that is self-sealing against the radially contoured side wall having the shelf in the valve manifold when acted upon by a vacuum, said second wing of said butterfly valve further having second elastic sealing means mounted on the periphery for providing a fairly low-leakage air seal, said second sealing means being constructed of an elastic material and including a beam portion for bending upon contact with the shoulder in the port in the valve manifold, each butterfly valve further including third elastic sealing means axially positioned at each side of said passage and radially provided to a predetermined extent thereabout for sealing said butterfly valve axially during rotation of the shaft.   
     
     
       2. A low-leakage air valve assembly as recited in claim 1, wherein said third elastic sealing means includes an angled sealing surface constructed to be in full compression when a corresponding valve is in a seated position. 
     
     
       3. A low-leakage air valve assembly as recited in claim 2, wherein said third elastic sealing means further comprises a ridge on the angled sealing surface thereof only on an underside of the butterfly valve. 
     
     
       4. A low-leakage air valve assembly as recited in claim 2, wherein said angled sealing surfaces is at an included angle relative to the shaft. 
     
     
       5. A low-leakage air valve assembly as recited in claim 2, wherein said third elastic sealing means further comprises a plurality of ridges on the angled sealing surface. 
     
     
       6. A low-leakage air valve assembly as recited in claim 1, wherein said beam portions of said second elastic sealing means further comprises a substantially flat portion only on an upper side of the butterfly valve. 
     
     
       7. A low-leakage air valve assembly as recited in claim 6, further comprising a ridge on said substantially flat portion of said second elastic means for increasing sealing stresses. 
     
     
       8. A low-leakage air valve assembly as recited in claim 6, further comprising a plurality of ridges on said substantially flat portion of said second elastic sealing means for increasing sealing stresses. 
     
     
       9. A low-leakage air valve assembly as recited in claim 1, wherein each of said butterfly valve further comprises reinforcement ribs on both sides thereof. 
     
     
       10. A low-leakage air valve assembly as recited in claim 1, wherein each port of said valve manifold is positioned at a slight angle relative to normal. 
     
     
       11. A low-leakage air valve assembly as recited in claim 10, wherein said angle ranges from about 10° to about 65°. 
     
     
       12. A low-leakage air valve assembly as recited in claim 11, wherein said angle is about 65°. 
     
     
       13. A low-leakage air valve assembly as recited in claim 1, wherein each port is substantially rectangular in shape. 
     
     
       14. A low-leakage air valve assembly as recited in claim 13, wherein each port has radially contoured side walls. 
     
     
       15. A low-leakage air valve assembly as recited in claim 1, wherein a first area defined by said first wing of said butterfly valve and said first elastic sealing means mounted on the periphery thereof is greater than a second area defined by said second wing of said butterfly valve and said second elastic sealing means mounted on the periphery thereof. 
     
     
       16. A low-leakage air valve assembly for an air intake manifold, comprising: a valve manifold having a plurality of ports therethrough with a channel extending across said valve manifold;   a shaft constructed for mounting within said channel of said valve manifold and rotation therein; and   a plurality of butterfly valves selectively spaced on said shaft to provide one butterfly valve for each port, each of said butterfly valves having a first and second wing with a first and second elastic sealing means mounted on a periphery of the first and second wings respectively, each butterfly valve further including third elastic sealing means axially positioned at each side of said butterfly valve and radially provided to a predetermined extent thereabout for sealing said butterfly valve axially with said respective port during rotation of the shaft.   
     
     
       17. A low-leakage air valve assembly as recited in claim 16, wherein said third elastic sealing means is positioned around about one-half of a lower side of said shaft. 
     
     
       18. A low-leakage air valve assembly as recited in claim 16, wherein said third elastic sealing means includes an angled sealing surface. 
     
     
       19. A low-leakage air valve assembly as recited in claim 16, wherein said first, second, and third elastic sealing means are formed integrally of elastic material. 
     
     
       20. A low-leakage air valve assembly as recited in claim 19, wherein said low-leakage air valve assembly is manufactured by a two step molding process comprising first molding plastic butterfly valves on said shaft, and then molding said first, second, and third elastic sealing means on each of said butterfly valves. 
     
     
       21. A low-leakage air valve assembly as recited in claim 19, wherein said low-leakage air valve assembly is manufactured by disposing plastic butterfly valves on said shaft and molding an elastomeric material thereon for said first, second, and third elastic sealing means. 
     
     
       22. A low-leakage air valve assembly as recited in claim 16, wherein each of said first elastic sealing means includes a projecting lip for sealing against a side wall with a shelf in each of the ports of said valve manifold.